Gordon Brown is facing two defeats from the unions at next week's Labour party conference over the failure to provide equal pay for millions of low-paid women workers in the public services and plans to close down half the state-owned Remploy factories for disabled people.

Ministers are working overtime to stop the conference passing motions from Unison, the biggest public sector union, over equal pay and a GMB motion over Remploy, which will be selected for debate next week. They thought they had agreed to allow the motions to be debated without a vote but the big four unions, the Amicus and T& G wings of Unite, Unison and the GMB, could still combine to ensure that they are passed - using their block 38% vote - for the last time to push through contemporary motions before they are abolished next year.

The GMB said yesterday it would press for a vote on its motion unless the government halted Remploy's closure.

Rival motions have been submitted by the constituency parties of ministers and former ministers with the aim of neutering criticism of the government.

The Unison motion says the equal pay law is "not fit for purpose" because tribunals cannot cope, and cites the fact there is still a 17% pay differential between men and women for the lowest paid public sector jobs, rising to 33% for part-timers. It also attacks the green paper from Hazel Blears, the communities and local government secretary, which calls for councils to become "enabling authorities", no longer providing public services themselves.

The GMB motion criticises Remploy's management for issuing redundancy notices to staff, accusing it of creating a "sense of insecurity and trauma, and ... the cruellest harassment of already very vulnerable workers". The Remploy closures are rapidly becoming a touchstone issue with activists: staff plan to demonstrate outside conference tomorrow. On Wednesday the union will announce the result of a ballot for strike action at the 83 factories which could become part of the campaign for a "winter of discontent".

The conference arrangements committee has culled a record number of 130 motions submitted for a ballot for debate this year. Eighty were removed, including a number of highly critical ones on the NHS, on British military aid to Colombia and criticism of the government for allowing the US to use the Menwith Hill base in North Yorkshire for a new missile system.

Next week's agenda

Sunday Alastair Darling will make his first speech as Labour chancellor. He may come under pressure to explain his role in the Northern Rock affair.